Enhancement like what? Speed? ADHD meds like Joe Haden? How about the drug from that movie Limitless? Some military-grade, super soldier shyte?
My post deals with the latest strongest science in restructuring the brain = non-drug, guided brain using itself to change itself. (Book: "The Brain That Changes Itself") Science, by studying how the brain grows itself = 1 into a concert pianist: 2 into a brilliant particle physicist: 3 into famous sculptor: etc It's happened all around us, all our lives, --(and before & after us.) You think those people #1,#2,#3 took drugs to acquire "enhanced" performing abilities in their fields. The frontiers of brain science advance faster than I can keep up with.
10-15 years ago a brain scientist-engineer invented and applied a tongue electrode that allowed any blind person to detect (see) the colors of any item he could hold his tongue against. His brain learned to train the sensory neurons in his taste-buds to sense the specific heat a color absorbs & so emits. So now that persons tongue neurons learned two functions now = detect flavors as well as detect ("see") colors. Did your brain need to take drugs to drop thinking like a child and start all the complex wired neural networks that adult thinking requires. That "seeing tongue" exploration seems silly to superficial observers but note that it is frontier work, involving understanding the brain's capabilities of creating new neurons self-designed for new purposes.
This "tongue" neuro-surgeon-engineer-scientist's first creation was the cochlear implant which requires the person's brain to retrain itself to match the artifi'cial electronic-sounds in which our sound "Henry" gets to him as "grockgree". Via the miracles of how the brain learns through natural biofeedback when they hear "grockgree" their complex hearing "module" actually recognizes - hears "Henry". That's a crude explanation but the scientific explanation takes 63 pages. The cochlear implant has given many grateful deaf people the blessing of hearing.
Science centers, without drugs are teaching stroke victims to regain digital dexterity. Google "mirror box" for stroke victims. You can make that with a 1' x 2' mirror and a cardboard box. So stroke victim has shriveled use of his left hand. He sticks both hands through 2 holes in the box, divided down the middle with the mirror reflecting his dexterous right hand. But that mirror reverses the image so he's looking back forth between his real right hand & its reflection that looks to him (= his brain) like it's his left hand ( btw, the left half of the box has top flap closed so his brain can't see his crippled left hand.). Now for learning he's given items to manipulate with good right hand but stares at the mirror where his brain "sees" his left hand doing the manipulations perfectly. Later, with his physical therapist, outside the box, he starts to swiftly regain proper use of his stroke hand, which is less contorted now. There's much more but this is already too much blah-blah. Sorry.
Contrary to the common media-messages, the bulk & most peer respected brain science sees drugs as destructive brain science i.e. hampers the neuro-genesis that rescues normality or advances natural enhancement.